Electric switch



C. HATAY ELECTRIC SWITCH Oct. 10, 1933.

Filed April 26, 1932 INVENTOR A'ITORNEY Patented Oct. 10, 1933 ELECTRIC swrrcn Charles Hatay, Berlin-Charlottenburg, Germany,

assignor to General Electric Company, a corporation of New York Application April 26, 1932, Serial No. 607,646, and in Germany May 1, 1931 3 Claims.

The present invention relates to' electric switches and more particularly the invention relates to such switches of the, liquid flow type in which the movements of a magnetizable body are availed of to make and break the electrical contact between the electrodes of the device.

'It is usual in such devices to attach the magnetizable body to suitably shaped body of insulation material to make up a plunger in the container of the device. It has been the practice in the art heretofore to make the plunger of such weight that it is immersed in the conducting fluid in the container of the switch so that the switch is normally in a contact making position, the plunger being moved to a contact breaking position by means of a magnet coil acting on the core of said plunger. In switches operating in this manner and of large current carrying capacity the plunger is of such great weight that the movements thereof are injurious to the glass container of the device during the operation and shipment of the device.

The object of the present invention is to provide a switch of the above type and operating in the manner above described in which the plunger is lighter in weight than those now known in the art. Another object of the invention is to provide a switch of this type capable of transmitting large currents which may be safely operated and transported. A further object of the invention is to provide a switch of the above type which is smooth and positive in operation. Still further objects and advantages attaching to the device and to its use and operation will be apparent to those skilled in the art from the fol-- lowing particular description and from the appended claims.

The invention attains its objects'by using a spring member of suflicient tension to overcome the buoyancy of the plunger in the mercury to maintain the, plunger in its immersed or contact making position in the container of the device. The particular shape and arrangement of the various parts of the new and novel switch will be apparent from an inspection of the accompanying drawing and a perusal of the following description thereof.

The drawing is a sectional side elevational view of the new and novel switch made in accordance with the invention.

Referring to the drawing the switch comprises a container 1 having electrodes 5 and 6 sealed therein at each end thereof and a body of mercury 4 therein. A plunger 2, 3 is arranged in said container 1 said plunger 2, 3 consisting of a cylindrical metal core 2 attached to an annular, straight-sided trough member 3 of insulation material such as quartz, for example. The side 3' of said trough member 3 is greater in diameter and in length than the iimer side 3" thereof and said core 2 is attached to the top of said side 3'. Said electrode 5 has two prong members and a cylindrical part 7 at the end of said prong members, said cylindrical part 7 is immersed in the mercury in said trough member 3 at all operating positions of said plunger 2, 3 and is concentric with side 3" the inner diameter thereof being'slightly greater than the outer diameter of said side 3". A spiral spring 8 surrounds side 3" and is located between and presses against the lower cylindrical part 7 of said electrode 5 and the lower interior part of said trough 3, and the strength of said spring 8 is suflicient to overcome the buoyancy of said plunger 2, 3 in said body of mercury 4 and thus maintains said plunger member 2, 3 in its contact making position in said container 1 which position is shown in the draw- When it is desired to move said plunger 2, 3 to its contact breaking position coil 2 is energized by closing the switch illustrated which'attracts and moves upward the core 2, and therewith the plunger 2, 3 compressing spring 8. The body of mercury in trough member 3 is then separated from the body of mercury in container 1 and thus the electrical contact between said electrodes 5 and 6 is broken. When the switch controlling coil 2' is opened plunger 2, 3 is forced back to its contact making position in container 1 by spring 8. The separation and uniting of the mercury body 4 takes place at the rim of trough part 3" and therefore the spark resulting from the make and break of electrical contact between said electrodes 5 and 6 takes place at that rim part. The container 1 is protected from this spark by the side 3 which is greater in length than said side 3".

By virtue of the structure above described I am able to make the plunger 2, 3 of extremely light weight as compared to plungers of prior devices operating in the same manner, and therefore the device is transported and operated with greater safety than in prior devices of the same type. Spring 8 maintains the plunger 2, 3 in a fixed position in said container 1 to avoid injury to said container during transportation thereof. As all the parts, container 1, cylindrical electrode part '7, spring 8, and plunger 2, 3 have the same vertical median line there is no likelihood of the plunger 2, 3, jamming during the operation of the device and the device is smooth and positive in operation. The insulation trough part 3 of the plunger 2, 3 is made of any suitable material and is, for example, quartz. The tension of spring 8 is just suiiicient to maintain plunger 2, 3 in its contact making position in said container 1, to keep the current consumption of coil 2 to a minimum.

While I have shown and described and have pointed out in the annexed claims certain novel features of the invention, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its use and operation may be made by those skilled in the art without departing from the broad spirit and scope of the invention, for example, the switch may be a gas filled switch or a vacuum switch as desired.

What I claim as new and desire to secure by Letters Patent of the United States is:-

1. A switch comprising a container, electrodes sealed therein,- a body of mercury therein, a plunger therein, a spring pressing against said plunger to maintain said plunger in a fixed position in said container during the transportation of said switch, said plunger having a core and adapted on successive movements thereof to make and break the electrical contact between said electrodes.

2. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a

plunger therein, a spring arranged between, and pressing against one of said electrodes and said plunger to maintain said plunger in a fixed position in said container during the transportation of said switch, said plunger having a core and adapted on successive movements thereof to make and break the electrical contact between said electrodes.

3. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a plunger therein, and a spring adapted to limit the movements of said plunger in said container during the transportation of said switch.

CHARLES HATAY. 

